Sediment enters streams from bank erosion, construction site runoff, and breakdown of impervious surfaces like roads and parking lots. Once in the stream, sediment covers delicate streambed habitat and eventually drops out in the stream creating diversions like point bars. Later sediment has to be removed from the water in the treatment process which can be costly.
Habitat Alteration or Inadequate Streamside Buffer
The riparian zone or streamside buffer is the zone of vegetation alongside a stream. The riparian zone is part of the stream and plays a huge role in maintaining the health of a stream. The vegetation helps hold the bank in place while regulating water temperature by shading the stream. Organic material also provides energy for aquatic life. A water quality protection area (WQPA) was established to protect this vital part of the stream during development. In Rutherford County, agricultural land was often farmed to a streambank leaving many streams without buffers. Development in these areas often requires the establishment of a WQPA on stream segments which may have seen erosion problems for many years.
A stream can have high nutrient levels for many different reasons including runoff from highly fertilized yards to agricultural runoff. High levels of nutrients in a stream can promote algal growth which depletes oxygen.